As with other drugs, the medical complications of cocaine may vary depending on the individual, frequency of use, amount of dosage, and/or prior medical attributes.

Crash and Withdrawal

Upon termination of heavy or prolonged cocaine use, a crash typically ensues, though it is usually less protracted than the crash associated with MA.[1] Withdrawal symptoms can then start relatively quickly, in part because cocaine has a short half-life. The DSM-IV defines cocaine withdrawal as consisting of depressive moods and at least two of the following symptoms [2-5]:

Fatigue

Vivid, unpleasant dreams

Insomnia or hypersomnia

Increased appetite

Psychomotor retardation or agitation

There is a correlation between cocaine withdrawal and the severity of addiction. It has been reported that those who experience withdrawal symptoms, when compared to those who did not, had greater problems regarding cocaine dependence.[2-4]

Cardiovascular

The cardiovascular system is the system most often adversely affected by cocaine use.[6]

Chest pain and myocardial infarction (MI)
Chest pain is the most common cardiovascular problem reported by cocaine users. Cocaine-related MI occurs due to alpha and beta adrenergic effects caused by blocking norepinephrine reuptake. These effects include increased heart rate and blood pressure, and coronary vasospasm with decreased oxygen delivery leading to myocardial ischaemia.[6,7]

It can take minutes or days for acute coronary events and MI to occur after cocaine use. However, the highest risk for MI is in the first hour of cocaine use. MIs induced by cocaine often occur in patients with normal coronary arteries.[6]

Cardiac arrhythmias
The arrhythmias reported are usually temporary and terminate once cocaine is metabolized.[6,7] The arrhythmias reported include:

Sinus tachycardia and bradycardia

Supraventricular arrhythmias

Bundle branch block

Ventricular fibrillation or asystole

Ventricular tachycardia

Torsade de pointes

Cardiomyopathy and myocarditis
Dilated cardiomyopathy is caused by the toxic effects of cocaine on the heart causing heart failure due to myofibrils destruction, interstitial fibrosis, and myocardial dilation.[6] Studies have shown that there has been a 20 to 30 percent incidence of myocarditis in patients who have died with detectable levels of cocaine in their system.[6,8,9] It should be noted that any young person with heart failure and cardiomegaly should be seen as a cocaine misuse possibility.[6]

Endocarditis
Endocarditis, which is an infection of the heart valve, seems more likely to develop in intravenous cocaine users than in any other intravenous drug users.[6,10] It is caused when bacteria enters the bloodstream via unsterile needles and attaches itself to the heart valve. High fever and chills are common symptoms. If not treated in a timely manner, endocarditis can be fatal.[10]

Aortic Dissection
Acute aortic dissection can be caused by the use of crack cocaine. It can also be the possible cause of chest pains in cocaine users.[6]

Sudden Death

Cocaine users who have died suddenly have been reported as having varying lethal doses and blood levels. Mechanisms responsible for sudden death may be [11]:

Arrhythmias

Status epilepticus

Centrally mediated respiratory arrest

Intracerebral hemorrhage

Pulmonary

The majority of pulmonary complications associated with cocaine use can be attributed to administration via inhalation. Pulmonary complications that have been associated with cocaine use are [6,11]:

Pulmonary edema

Asthma

Pulmonary hemorrhage

The presence of alveolar macrophages loaded with hemosiderin

Bronchiolitis obliterans

It has been reported by cocaine users that having another person forcefully blow smoke (cocaine vapors) into one’s mouth intensifies the effects, most likely due to greater distribution in pulmonary circulation. This practice has been associated with causing barotrauma, including pneumothorax, pneumomediastinum, and pneumopercardium.[11]

The lungs of freebase cocaine smokers usually have a decreased ability to transport oxygen into the blood. This may be due to cocaine’s ability to cause vasoconstriction.[10] Also, “crack lung,” an acute pulmonary syndrome caused by inhalation of free-base cocaine, can instigate chest pain, shortness of breath, or the coughing up of blood.[10,12] These symptoms can occur immediately after smoking crack or up to 48 hours after crack was last used. Only some people need medications or mechanical ventilation to recuperate from crack lung, others spontaneously get better.[10]

Nasal Problems

Since cocaine is a vasoconstrictor, intranasal cocaine use leads to decreased blood flow to the nose, thus causing the mucous membranes of the nose to become irritated and inflamed. In addition, ulcers may develop inside the nostrils. Some symptoms include chronic sneezing, frequent nose bleeds, and nasal congestion. Long term intranasal cocaine use can cause tissue death and consequently lead to perforation of the nasal septum.[10]

Neurological

The most common complication reported by cocaine users is headaches, which can occur during cocaine use or withdrawal. Partial and generalized seizures have also been reported with cocaine use, most of which are associated with smoking crack or with intravenous administration of cocaine.[6,11]

Hemorrhagic strokes have been associated with the use of cocaine hydrochloride (cocaine in powder form that is typically snorted). On the other hand, crack cocaine (which is typically smoked) is more likely to induce cerebral infarctions than cocaine hydrochloride possibly because the concentration of cocaine in the blood is higher when it is smoked versus snorted. Long term cocaine users may develop cerebral atrophy mostly occurring in the frontal and temporal areas.[11]

Renal

The most common renal complication of cocaine use is acute renal failure due to rhabdomyolysis with no or relatively mild neuromuscular symptoms.[11]

Gastrointestinal

The following are some of the intestinal disorders that have been associated with cocaine use [6,11]:

Intestinal ischemia after oral, intravenous, and intranasal cocaine use

Gastroduodenal perforations in young patients using crack

A few cases of colitis

Cocaine trafficking can involve ingestion of cocaine-filled packets or balloons which may rupture. The management of “body packers” is a controversial issue. Previously, it was recommended that the packages be removed via surgery, however, now a more conservative management recommends surgery for only those patients who have developed obstruction or perforation.[11]

Endocrine

Due to the increase in dopamine levels followed by cocaine administration, there is a decrease in prolactin secretion. When long term use or withdrawal of cocaine is experienced, dopamine levels decrease and hyperprolactinemia results.[11]

Obstetric

Cocaine use during pregnancy may be associated with an increased risk for [6,11,13]:

Placental abruption

Lower birth weight

Pre-term delivery

Spontaneous abortion

Microcephaly

Congenital urologic abnormalities

Neurobehavioral dysfunction

Sudden infant death syndrome (SIDS)

Sexual Function

Various effects are produced by cocaine on sexual function. Some cocaine users report enhanced sexual function and some report inhibited sexual function. Greater sexual arousal and prolonged stamina during intercourse can be experienced by persons while using cocaine. Compulsive sexuality has also been associated with cocaine use.[11]

In regard to male sexual function, erectile difficulties have been associated with greater and longer term cocaine use. The most common effect is delayed or inhibited ejaculation.[11]

Psychiatric Effects and Lifestyle

Repeated high-dose use of cocaine has been noted to cause depression and anxiety among users who were not previously depressed.[10] Individuals who use large amounts of cocaine (more than 100mg) may eventually lose touch with reality and experience auditory hallucinations. They may also exhibit bizarre, erratic, and violent behavior, as well as paranoia and psychosis.[14]

Complications due to cocaine-related psychiatric effects and life-style include [10]: